System to control a rotary electric machine

Patent metadata

Field	Value
Publication number	US-10666182-B1
Application number	US-201815947540-A
Country	US
Kind code	B1
Filing date	Apr 6, 2018
Priority date	Apr 6, 2018
Publication date	May 26, 2020
Grant date	May 26, 2020

Abstract

A control system for a rotary electric machine includes a controller configured to generate dynamic input current data based upon a dynamic analysis of self flux data, mutual flux data, and saturation scaling factor data. Upon generating a torque request, the controller is configured to determine a desired electrical input based upon the dynamic input current data to generate the desired output torque. The desired electrical input includes a magnitude and duration of an electrical pulse and a desired angular position of the rotor of the rotary electric machine relative to the stator of the machine. The controller determines an angular position of the rotor and generates an operating command to generate the desired electrical input at the desired angular position of the rotor to propel the rotary electric machine and generate the desired output torque. A rotary electric machine and method of operating same are provided.

First claim

The invention claimed is:

1. A control system for a rotary electric machine, the rotary electric machine comprising a stator having a plurality of stator poles, a plurality of coils wrapped around the plurality of stator poles, and a rotor having a plurality of rotor poles, the rotor being rotatable relative to the stator, the control system comprising:
a rotor position sensor configured to determine an angular position of the rotor relative to the stator;
a controller configured to:
access a plurality of characteristics of the rotary electric machine, the plurality of characteristics including a number of the plurality of stator poles, a number of the plurality of rotor poles, a number of electrical phases, and a number of windings of each of the plurality of coils;
access a plurality of self flux data, the plurality of self flux data being a function of the angular position of the rotor;
access a plurality of mutual flux data between an energized electrical phase and a non-energized electrical phase of the rotary electric machine, the plurality of mutual flux data being a function of the angular position of the rotor;
access a plurality of saturation scaling factor data, the plurality of saturation scaling factor data being based upon the plurality of self flux data;
generate a plurality of dynamic input current data based upon a dynamic analysis of the plurality of self flux data, the plurality of mutual flux data, and the plurality of saturation scaling factor data;
generate a torque request corresponding to a desired output torque;
determine a desired electrical input based upon the plurality of dynamic input current data to generate torque corresponding to the desired output torque, the desired electrical input including a magnitude and duration of an electrical pulse and a desired angular position of the rotor relative to the stator;
determine an angular position of the rotor based upon the rotor position sensor; and
generate an operating command to generate the desired electrical input at the desired angular position of the rotor to propel the rotary electric machine and generate the desired output torque.

2. The control system of claim 1 , wherein the plurality of saturation scaling factor data is based upon a rate of change of the plurality of self flux data.

3. The control system of claim 2 , wherein the plurality of saturation scaling factor data is normalized to provide a maximum value of 1.0.

4. The control system of claim 1 , wherein the plurality of self flux data is further a function of a current supplied to an energized phase of the rotary electric machine.

5. The control system of claim 4 , wherein the controller is configured to generate the plurality of self flux data through a static analysis of the rotary electric machine.

6. The control system of claim 1 , wherein the plurality of mutual flux data is further a function of a current supplied to a non-energized phase of the rotary electric machine.

7. The control system of claim 6 , wherein the controller is configured to generate the plurality of mutual flux data through a static analysis of the rotary electric machine.

8. The control system of claim 1 , wherein the rotary electric machine includes three phases, and the controller is further configured to access a second plurality of mutual flux data between the energized electrical phase and a second non-energized electrical phase.

9. The control system of claim 8 , wherein the second plurality of mutual flux data is further a function of a second current supplied to a second non-energized electrical phase of the rotary electric machine.

10. The control system of claim 1 , further comprising a power source operatively connected to the plurality of coils to provide electrical pulses to the coils and wherein the desired electrical input includes a voltage pulse having a desired magnitude, timing and duration.

11. A method of controlling a rotary electric machine, the rotary electric machine comprising a stator having a plurality of stator poles, a plurality of coils wrapped around the plurality of stator poles, and a rotor having a plurality of rotor poles, the rotor being rotatable relative to the stator, the method comprising:
accessing a plurality of characteristics of the rotary electric machine, the plurality of characteristics including a number of stator poles, a number of rotor poles, a number of electrical phases, and a number of windings of each of the plurality of coils;
accessing a plurality of self flux data, the plurality of self flux data being a function of an angular position of the rotor;
accessing a plurality of mutual flux data between an energized electrical phase and a non-energized electrical phase, the plurality of mutual flux data being a function of the angular position of the rotor;
accessing a plurality of saturation scaling factor data, the plurality of saturation scaling factor data being based upon the plurality of self flux data;
generating a plurality of dynamic input current data based upon a dynamic analysis of the plurality of self flux data, the plurality of mutual flux data, and the plurality of saturation scaling factor data;
generating a torque request corresponding to a desired output torque;
determining a desired electrical input based upon the plurality of dynamic input current data to generate torque corresponding to the desired output torque, the desired electrical input including a magnitude and duration of an electrical pulse and a desired angular position of the rotor relative to the stator;
determining a rotor position based upon a rotor position sensor; and
generating an operating command to generate the desired electrical input at the desired angular position of the rotor to propel the rotary electric machine and generate the desired output torque.

12. The method of claim 11 , wherein the plurality of saturation scaling factor data is based upon a rate of change of the plurality of self flux data.

13. The method of claim 12 , wherein the plurality of saturation scaling factor data is normalized to provide a maximum value of 1.0.

14. The method of claim 11 , wherein the rotary electric machine includes three phases, and further including accessing a second plurality of mutual flux data between the energized electrical phase and a second non-energized electrical phase.

15. The method of claim 14 , wherein the second plurality of mutual flux data is further a function of a second current supplied to a second non-energized electrical phase of the rotary electric machine.

16. The method of claim 11 , wherein the desired electrical input includes a voltage pulse having a desired magnitude, timing and duration.

17. A rotary electric machine comprising:
a stator having a plurality of stator poles;
a plurality of coils wrapped around the plurality of stator poles;
a rotor having a plurality of rotor poles, the rotor being rotatable relative to the stator;
a rotor position sensor configured to determine an angular position of the rotor relative to the stator;
a controller configured to:
access a plurality of characteristics of the rotary electric machine, the plurality of characteristics including a number of the plurality of stator poles, a number of the plurality of rotor poles, a number of electrical phases, and a number of windings of each of the plurality of coils;
access a plurality of self flux data, the plurality of self flux data being a function of the angular position of the rotor;
access a plurality of mutual flux data between an energized electrical phase and a non-energized

Assignees

• Caterpillar Inc

Inventors

• Nino Baron Carlos E
• Khalil Ahmed
• Wai Jackson
• Gerdes Jesse R
• Sonth Sangameshwar
• Saad Amir

Classifications

• H02P21/18

  Estimation of position or speed · CPC title

• H02P6/185

  using inductance sensing, e.g. pulse excitation · CPC title

• H02P25/08 Primary

  Reluctance motors · CPC title

• H02P21/141

  Flux estimation · CPC title

• H02P25/086

  Commutation · CPC title